Accidents during commercial drilling operations are of great concern to safety organizations, labor unions, equipment suppliers, and most importantly rig operators. The most common accidents, as well as the most damaging, occur when the drill rig operator becomes entangled with the rotating drilling tools. Every year, drill rig operators lose limbs, and in some cases their lives, through carelessness and the lack of any currently available safety devices which automatically cut the power to the spindle in the event of an accident.
U.S. Pat. No. 5,085,280 discloses a shut-off mechanism for a drill rig which allows the drill operator to manually cut power to the drill spindle by tripping a wobble-type switch. While the drill rig of the '280 patent provides for an effective means for limiting the injuries suffered during an accident, neither that rig nor any other rigs currently on the market can prevent an accident before it happens. Additionally, kill switches of this type assume the operator will not panic and forget about the switch during an accident. Since the operator has only a very short time to react after the accident occurs, many operators can be seriously injured or killed even on rigs which have these safety features.